Non-invasive "drawable", or "paintable", electrode for electrical stimulation or biological signal sensing comprising a pervious and electrically conductive layer (1), at least one electrically insulating element (2) for maintaining the electrically conductive layer (1) separated from the skin (11), and a conductive material (3) that is deposed using a delivery system (4) on desired areas (5) of the electrically conductive layer (1). The conductive material (3) can penetrate the electrically conductive layer (1) and any other part of the electrode underlying the desired areas (5), thus reaching the skin. The conductive material (3) creates an electrical connection between the desired areas (5) of the electrically conductive layer (1) and the skin. Therefore, the shape of the desired areas (5) electrically connected with the skin, can be customized by the user deposing (or "drawing") the conductive material (3). Thus, the conductive material (3) enables the fabrication of electrodes with custom-shaped electrically conductive areas in desired positions.